Fig. 7.

miR‐558 markedly downregulated MMP17 and MMP1 expression through targeted regulation. (A) The targeted genes of miR‐558 were predicted through the TargetScan database, and the binding sites between miR‐558 and MMP1, MMP16, MMP17, and MMP24 were exhibited. (B) MMP1 and MMP17 expression was monitored by qRT–PCR in A549 and H1299 cells transfected with miR‐558 mimics. (C) Wild‐type and mutant MMP1 and MMP17 plasmids for miR‐558 were constructed, and the interaction was confirmed via luciferase reporter assay in 293T cells. (D) The effects of miR‐558 on the expression of MMP1 and MMP17 were identified by western blot assay in A549 and H1299 cells. (E,F) MMP1 and MMP17 expression was determined via qRT–PCR and western blot assays in A549 and H1299 cells transfected with siRNA pool. (G,H) qRT–PCR and western blotting analyses were carried out in A549 and H1299 cells cotransfected with anti‐miR‐558 and MMP1 or MMP17 siRNAs. Data represent the mean ± SD from three independent experiments. Student’s t‐test with two biological dependent or independent replicates was used to determine statistical significance; *P < 0.05, **P < 0.01